1. What is the Wattage Formula?

The wattage formula (P = V × I × PF) calculates electrical power in watts (W) from voltage (V), current (I), and power factor (PF). It's fundamental for understanding electrical power consumption and circuit design.

2. How Does the Calculator Work?

The calculator uses the wattage formula:

Where:

• \( P \) — Power in watts (W)
• \( V \) — Voltage in volts (V)
• \( I \) — Current in amperes (A)
• \( PF \) — Power factor (unitless, 0 to 1)

Explanation: For DC circuits or purely resistive AC loads, the power factor is 1. For AC circuits with reactive components, the power factor is typically between 0 and 1.

3. Importance of Power Calculation

Details: Accurate power calculation is essential for electrical system design, energy efficiency assessments, circuit protection, and proper equipment sizing.

4. Using the Calculator

Tips: Enter voltage in volts, current in amperes, and power factor (default is 1 for DC or resistive AC circuits). All values must be valid (voltage > 0, current > 0, 0 ≤ PF ≤ 1).

5. Frequently Asked Questions (FAQ)

Q1: What is power factor?
A: Power factor is the ratio of real power to apparent power in AC circuits, representing how effectively current is converted to useful work.

Q2: When can I assume power factor = 1?
A: For DC circuits and purely resistive AC loads (like incandescent lights or heaters), PF=1. For motors, transformers, or capacitive/inductive loads, PF is less than 1.

Q3: How does this relate to energy consumption?
A: Power (watts) multiplied by time (hours) gives energy (watt-hours). For example, 100W device running for 10 hours consumes 1,000Wh or 1kWh.

Q4: What's the difference between real and apparent power?
A: Real power (watts) does actual work. Apparent power (VA) is the product of V and I. Their ratio is the power factor.

Q5: How do I measure these values?
A: Use a multimeter for V and I. Power factor meters or specialized wattmeters measure PF directly.